INVESTIGATIONS ON LIGHTS AND LIGHTHOUSES.
For some time past a series of observations and experiments have been carried on under the auspices of a Committee of the Elder Brethren of the Trinity House, at the South Foreland, chiefly relating to the measurement of lights by means of a photometer—the invention of Mr Vernon Harcourt—the standard light of which burns with wonderful regularity and uniformity. The Committee are now engaged on a still more interesting series of observations, which are made from the sea, and which will more nearly concern sailors. These experiments and observations for testing the capabilities of various lights will be peculiarly remarkable, as craft of almost all descriptions will be enlisted in this work: the mail-packets, the Peninsular and Oriental liners, pilot vessels of different nationalities, trading-ships, and French cruisers. The electric light, of course, is immensely superior to either gas or paraffine oil; but even this, from its whiteness and dazzling brilliancy, has not been found to be so very much better, in thick hazy weather, than either oil or gas, the reddish-yellow of the latter perhaps showing better through the haze of a sea-fog than the white glare of the former. All these points will, however, be carefully gone into, and every sort of test applied to discover the best and safest light to direct mariners to and by our coasts; and when all is completed, the Committee will record their useful labours in a full Report to the Board of Trade, a document which will possess peculiar interest for all who have at heart the welfare of ships and sailors.